Study on Seedling-stage Biomass of Provenances of Camptotheca acuminata

Based on 540 one year old sample seedlings from18 provenances of Camptotheca acuminata,the biomass of different organs and the relevant relationship among different organs were analysed.The results indicate that the proportions of the biomass(dry)of stems,branches,leaves,roots and barks were 29.54%,9.20%,30.75%,22.74% and 7.77% respectively,thus,the leaves has the highest proportion.Provenance 4 from Fujian,8 and 9 from Jiangxi and 11 and 12 from Hunan has considerably high biomass,among which provenance 8 from Nanchang City,Jiangxi Province has both highest total biomass and leave biomass.The regression equations of biomass to diameter at the base(D)and height of seedlings(H)were established for estimating the leave biomass(m1)and total biomass(m2):The four regression equations m=aDbHc,m=aDbeCH + d/H,m=a + D2(b + cH + dH2)and m=D2/(a + bD + cD2),especially the regression equation m=D2/(a + bD + cD2),can be used for estimating the leave biomass(m1)and total biomass(m2),with considreably accurate results.